Recording of mechano-electrical transduction currents by a nystatin perforated-patch method

Mechano-electrical transduction (MET) currents in isolated cochlear hair cells of chicks were recorded by use of a nystatin perforated-patch method. The membrane of a cell-attached patch was permeabilized by nystatin in the patch pipette, thus providing electrical continuity between the pipette and the cytoplasm of the cell without loss of cytoplasmic compounds. The current-voltage relationship was linear for the inward-going MET current at negative membrane potentials, but outward currents were reduced at positive membrane potentials, evidence of inward-going rectification. Elevation of the intracellular concentration of calcium at positive membrane potential, mediated via a voltage-dependent Ca2+ channel, may suppress the outward-going MET current by acting from within the cell.